Weird visual bug Persona 3 FES
#21
(07-02-2013, 10:39 AM)StriFe79 Wrote: actually FXAA is Nvidia's FSAA, whereas MSAA is AMDs.

MSAA is MUCH MORE EFFECTIVE THAN FXAA

MUCH

IT'S NO WAY IT'S THE SAME !
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#22
(07-02-2013, 10:39 AM)StriFe79 Wrote: actually FXAA is Nvidia's FSAA, whereas MSAA is AMDs.

Err... no.

FXAA stands for Fast Approximate AA. It's a post processing effect (it happens AFTER everything is rendered). It was made by an employee of nvidia and made available to the public to use on any card capable of OpenCL/DX10+

MSAA stands for Multi Sample AA. It's done DURING rendering. An algorithm takes multiple samples and... well... wikipedia says it best.

Quote:When a fragment is rendered with multisample anti-aliasing, if any of the multi sample locations in a pixel are covered by the triangle that created it, a shading computation must be performed for that triangle. Shading inputs (texture coordinates, etc) are interpolated from values stored at the triangle's vertices, usually using the pixel center as the sample point. If the pixel center is outside the triangle, shading inputs are extrapolated. Extrapolation can be avoided by using centroid sampling, where the shading inputs are sampled at the covered multisample location nearest to the pixel center, but may result in non-uniform screen space sampling near edges.[3]

FSAA stands for Full Scene AA. It was the first of the "true" AA techniques, and is now more commonly referred to as SSAA (SuperSampling). It's the technique used when rendering to a larger size than is actually being displayed. It works by taking the extra information from the additional points of reference, then blending them together. Unless MSAA, which is designed to work mostly on edges (and thus save bandwidth) it does the entire picture so everything comes out sharper. It's also the safest because the algorithms can't "mess up" like edge detect methods do. It also isn't just a blanket "blur" filter which removes details from objects like FXAA.

There are of course, MANY other types of AA, but these three are the most common...

Basically, if you had a machine with unlimited power FSAA/SSAA would always be the best, but when you are literally exponentially growing how much work you have to do to render an image (FSAAx2 is actually 4x the workload. FSAAx4 is actually 16x the workload!!).

MSAA, as discussed before, is designed to look for edges and work only on them, greatly reducing the amount of effort required to render something, but at the cost of accuracy... also it HATES transparencies (which is why it reacts so badly to shadows in PCSX2 and thinks like trees/foliage in many PC games as well). PC games have to go out of their way to accomodate MSAA (and indeed, that is why Unreal engine 3 doesn't even allow for it!) or else it borks their games up bad.

FXAA is definitely dead last. In most cases it's better than nothing, but you're giving up some graphical fidelity to try and diminish those jaggies.
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#23
(07-02-2013, 10:39 AM)StriFe79 Wrote: actually FXAA is Nvidia's FSAA, whereas MSAA is AMDs.

I really don't think it was introduced by AMD.
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